Pressure impulse dampener



1932. E. s. PEARCE ET AL PRESSURE IMPULSE DAMPENER Original Filed Oct. 21, 1925 'ZW BY 1 4 W M ATTORNEY ratented Dec. 13, 1932 hurrah STATES PATENT ()FFICE EDVIIN S. PEARCE AND EDMOND C. KARIBO, OF INDIANAPOLIS, INDIANA rREssURE IMPULSE DAMPENER' 'Cvriginal application filed October 21, 1925, Serial 'No. 63,827. Divided and this application filed October 26,

1929. Serial This invention relates to pressure'impulse dampeners, and involves a construction which is particularly useful in association with fiuid-pressure-actuated devices, where the pressure of the fluid is pulsating or irregular, while the device acted upon by the fluid should operate without violent momentary fluctuations.

An example of such use of the present invention is well illustrated by our co-pending application, fierial No. 63,827, filed October 21, 1925, issued as Patent No. 1,737,199, November 26th, 1929, for indicating apparatus for locomotive back pressure (of which the present application is a division). In that application there is illustrated an indicator, actuated by the exhaust pressure of a steam locomotive to give continuous direct indication to the engineman as to how he should operate the reverse lever of the locomotive to maintain the optimum mean back pressure. The pulsating exhaust, before passing to the indicator, is passed through the pressure impulse dampener, or choke, embodying our present invention, to effect a smoothing or ironing out of the severe exhaust impulses of the locomotive.

This invention therefore involves, pri marily, the damping of pressure impulses in a. fluid-pressure line, especially in order to deliver to a device to be operated by the fluid a more uniform pressure so as to effect smooth operation of the device and to protect it from excessive fluctuations or vibrations.

More specifically, the invention involves the attainment of the foregoing by an effective, simple and inexpensive device; which is compact so as to fit into a small space; and easy to assemble, install, inspect, clean and repair; and which can be readily accommodated to any particular pipe-line arrangement in which it is to be used, and this without necessitating additional couplings, elbows or other pipe joints.

The invention still further involves the provision of such a device which is as rugged as it is simple, in which certain elements may be made counterpart and interchangeable, and which by its general arrangement naturally permits a drainage of condensate therethrough.

How these objects and advantages are attained, together with others which are incident to the invention orwhich will occur to those skilled in the art, will be evident from the following description taken together with the accompanying drawing, in which drewing:

Fig. 1 is a somewhat diagrammatic side elevational view of a locomotive illustrating one application of our invention;

Fig. 2 is a detailed view, partly inside elevation and partly in longitudinal section, of the damping device embodying our invention; and

Fig. 3 is a transverse section of the device, taken on the line 3-3 of Fig. 2.

Referring first to Fig. 1, it will be seen that we have illustrated a locomotive 2, from the exhaust cavities 3, of which suitable piping a, 4. conveys exhaust steam to a common plpe 5. The pipe 5, extending back to the indicator or other pressure-operated device'G in the cab 7, may conveniently be placed beneath the sheathing or lag-covering 8 of the locomotive boiler, as shown, to minimize pressure variations from changes in temperature and to preserve a neat appearance.

Our pressure impulse dampener, indicated generally, in Fig. l, by reference numeral 9, being small and compact, may be placed at any convenient point in the line 5 and lends itself readily to location under the sheathing 8 if desired. As will further appear hereinafter, from the detailed description of the device, its construction also makes possible its convenient connection into the pipe-line 5, many other point of use, without necessitating additional bends, elbows or fittings in the pipe in which it is inserted.

By reference now to FigsQ and 3, it will. appear that the damping device is of a very simple and rugged construction, easy to assemble and to take a art for cleanin and constructed of a minimum number of parts. The casing or wall 10 is equipped at each end with a cap piece 11, and centered by these caps, within the chamber 12 thus formed,:is a baflle or screen 13 havinga ring 14 within it through which the bolt 15 passes, this bolt being extended through both caps and clamping the whole structure firmly together by means of the nut 16. The two caps 11 are identical, each having a lateral 6X- tension or pipe connection 17 which is formed with a restricted passage or nozzle 18 toward the inside. A valuabie feature of the dampener, bearing on the ease of assembly and actual installation of the device, is the construction of the cap-pieces, which may be turned through any degree relatively to each other or to the cylindrical shell (as seen in dot-and-dash lines at 17a in Fig. 3) while at the same time the planes of the inlet and out let ports remain parallel, thus obviating the necessity for elbows and other fittings in the connecting piping, as is evident from Figs. 1 and 2.

The positioning of the screen 13, between the counterpart cap-pieces 11, is positive both as to endwise and lateral location, since the ends thereof seat within the sockets or recesses 18. Furthermore, the mid-portion of the screen is additionally supported by the annulus 1 1, which is centrally apertured to fit the bolt 15, and peripherally grooved to fit the constriction or internal shoulder 19 of the screen. The annulus, as will now ap pear, further serves the purpose of a battle to direct the flow of pressure fluid.

In the application of the invention in the way illustrated in the drawing (and with particular reference to Fig. 2) the pulsating iiuid is admitted to the dampener through the lower connection 17 and its port 18, which decreases in diameter inwardly and initially tends to smooth out the impulses, and thence into the space 13c, on one side of ring 14, inside the screen or foraminous members 13. Passing outwardly through the openings of the screen, it then flows upwardly through the annular chamber 12, back through the screen 13, on the other side of ring let, into chamber or space 18?), and then out through the upper port 18, which, widening outwardiy, acts to reduce the velocity of the now smoothed-out pressure stream as it leaves the device.

lVc have found that the indie and screen arrangement, in conjunction with, and positioned between, ports which are oppositely tapered with respect to the direction of flow, provides very eiiective damping as compared with devices heretofore used. The construction of the device as an elongated chamber, with inlet and outlet connections extending laterally at each end thereof, permits the simplest possible mounting of the device, in a vertical position, between two sections of substantially horizontal (or slightly sloping) pipe, such as in the assembly of Fig. 1, which provides for automatic natural drainage of condensate down into the lower pipe section.

The securing of the parts by a single centrally-disposed retaining means or bolt insures an even pressure on the circumferential juncture of shell 10 and caps 11 to keep the joints tight; permits the opening of the housing for inspection, repair, or cleaning out of carbon deposits, without the necessity of dis connecting the pipe connections; and permits of an gularly disposing the pipe sections with respect to one another at any angle in the 360 around the circumference of the barrel, according as the installation may require.

lVhat we claim is 1. A fluid-pressure-pulsation dampener comprising a casing; a tubular screen positioned Within and longitudinally of said casing; an ii'iwardly extending annular member in said screen; a removable cap at each end of the casing having a central aperture, a laterally extending tapered port and a shoulder abutting against said screen; and a retaining member extending through said cap apertures and said annular member.

2. A fluid-pressure-pulsat1on dampener comprising a casing; a tubular screen positioned within and longitudinally of said casing; baille means in said casing cooperating with said screen intermediate the ends of the latter to support the same and guide the fluid; a removable cap at each end of the casing having a center aperture, a laterally extending tapered port and a shoulder abutting against said screen; and a retaining member extending through said cap apertures and said baffle means.

3. A fluid-pressure-pulsation dampener comprising a tubular casing, battle means therein, counterpart inlet and outlet heads at the ends of said casing provided with inlet and outlet connections disposed in substantially parallel planes transverse said casing and radially oi? the longitudinal axis of the latter, said battle means being positioned by said casing and by said heads, and means of relative angular abutment between the radially extending connections of said heads, said adjustment means including a rotational mounting tor at least one of said heads and a releasable through bolt extending centrally through said heads and longitudinally through said tubular easing.

In testimony whereof we have hereunto signed our names.

EDlVIN S. PEARCE. EDMOND C. KARIBO.

CERTEFIGATE OF CORRECTION.

Patent No. 1,891,008. December 13, 1932.

EDWIN S. PEARCE ET AL.

.It is hereby certified that error appears in the printed specification of the i above numbered patent requiring correction as follows: Page 2, line 40, for

"members" read "member"; and line 109, claim 3, for "abutment" read "adjustment"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 24th day of January, A. D. 1933.

. Mr J: Moore,. (Seal) Acting Commissioner of Patents. 

